It is often desirable to measure the vibration of an object to evaluate how the object is performing. An excess amount of vibration can indicate possible problems. One type of device for measuring the vibration of an object is a laser doppler vibrometer (LDV). A LDV measures the vibration of an object without contact. Basically, a LDV works by reflecting a laser signal off of a surface of an object. The LDG then compares the frequency of the reflected signal with the original signal. A change in frequency (Doppler shift) indicates vibration (or movement) of the object. Moreover, the measured change in frequency is used to calculate the vibration of the object.
Although LDV devices work in many applications their use has some limitations. For example, it is difficult to align light sensors of the LDV to receive the reflected laser light. Moreover, it is difficult with current LDV designs to obtain vibration measurements in multiple dimensions or multiple directions.
For the reasons stated above and for other reasons stated below, which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for a vibration detection system using a LDV that provides for easy sensor alignment and vibration measurements in multiple dimensions.